About The Cover

COVER Artist's conception of gamma-ray burst (GRB) 130427A, one of the brightest and longest-lived GRBs observed to date. GRBs such as this one occur when the core of a massive star runs out of nuclear fuel, collapses, and forms a black hole that drives a powerful jet of plasma traveling close to the speed of light. See pages 34, 38, 42, 48, and 51. Image: NASA/Fermi and Sonoma State University/Aurore Simonnet